Apparatus for soaking steel pieces

Abstract

An apparatus for soaking steel pieces including cold steel pieces and hot steel pieces. The apparatus is of the type which includes: a soaking furnace for subjecting the steel pieces to a soaking treatment; a preheating chamber for preheating the cold steel pieces before the cold steel pieces are introduced into the soaking furnace, the preheating chamber being connected to the soaking furnace for receiving waste heat from the soaking furnace for the preheating treatment and having an outlet portion for discharging the cold steel pieces; and a mechanism for introducing the steel pieces into the soaking furnace and for advancing the steel pieces through the soaking furnace. The soaking furnace has: a heating zone for heating the steel pieces; a soaking zone being communicated to the heating zone and having a heat source for heating the steel pieces, which have been heated in the heating zone, at a higher temperature than in the heating zone for the soaking treatment, the soaking zone having a ceiling higher than a ceiling of the heating zone; and means for connecting the heating zone to the preheating chamber for feeding waste heat.

What is claimed is: 
     
       1. An apparatus for soaking steel pieces including cold steel pieces and hot steel pieces, the apparatus being of the type which includes: a soaking furnace for subjecting the steel pieces to a soaking treatment; a preheating chamber for preheating the cold steel pieces before the cold steel pieces are introduced into the soaking furnace, the preheating chamber being connected to the soaking furnace for receiving waste heat from the soaking furnace for the preheating treatment and having an outlet portion for discharging the cold steel pieces; and means for introducing the steel pieces into the soaking furnace and advancing the steel pieces through the soaking furnace, the improvement wherein the soaking furnace comprises: (a) a heating chamber having a first ceiling, first sidewalls and one end having an inlet for the steel pieces;   (b) a soaking chamber integrally formed with the heating chamber, the soaking chamber communicating with the heating chamber so that the heat energy is fed from the soaking chamber to the heating chamber and so that the steel pieces are movable from the heating chamber to the soaking chamber, the soaking chamber having a second ceiling, second side walls, heating means for heating the steel pieces and an outlet, formed at one end thereof remote from the heating chamber, for discharging the steel pieces, the soaking chamber being aligned with the heating chamber along a line of travel of the steel pieces from the inlet of the heating chamber to the outlet of the soaking chamber;   (c) means for connecting the one end of the heating chamber to the outlet portion of the preheating chamber for feeding waste heat from the heating chamber to the preheating chamber, and wherein;   the soaking chamber defines a unitary space, the heating means is disposed at an upper portion of one of the second side walls of the soaking chamber; and the second ceiling of the soaking chamber is higher than the first ceiling of the heating chamber, whereby a radiative heat zone is produced at a portion near the second ceiling within the soaking chamber when the heating means is operated, thus soaking mainly by radiative heat transfer the steel pieces, which have been heated in the heating chamber mainly by convective heat transfer due to the heat energy fed from the soaking chamber, at a higher temperature than in the heating chamber.   
     
     
       2. An apparatus for soaking steel pieces as recited in claim 1, wherein the soaking furnace is disposed to be perpendicular to the preheating chamber with respect to the line of travel of the steel pieces, and wherein the connecting means is a flue for feeding the waste heat from the heating zone to the preheating chamber. 
     
     
       3. An apparatus for soaking steel pieces as recited in claim 2, wherein the connecting means is a duct having a damper incorporated therein for opening and closing the duct.